Funeral and deaths are regulated by the government and local municipal authorities for a variety of reasons.
Some of these are:
1. Sanitation
2. Government and most people like to make sure people died of natural causes and weren't just knocked off for some reason (makes most of us feel a little safer).
3. Most people hope they will be respected in death and that others will remember them. After alll, funerals and similar occassions are for the benefit of the living to help them grieve.
4. A significant number of people are employed in the funeral industry.